Method for producing spun yarn-like bulked yarns

ABSTRACT

Bulked yarns which have many uniform loops and snarls, and are excellent in spun yarn hand can be obtained by twisting plural yarns having difference in length of 3 to 40% in an optional direction at a twist coefficient of 10 to 140, rubbing thus twisted yarns to form loops and snarls in the longer filament yarn, and subsequently additionally twisting the yarns in the direction of the first twisting so that the twist coefficient becomes at least 5 to set the loops and snarls formed by the rubbing action.

United States Patent Kurata et al.

[ Dec. 30, 1975 METHOD FOR PRODUCING SPUN 3,526,084 9/[970 London er al51/157 TS x YARN-LIKE BULKED YARNS 3.645.080 2/1972 3,683,6l2 8/1972Buzano [75] Inventors: Taken Kurata; Tamotsu Hayazaki; 3,691,750 9/1972Waters Kyoko Murakami, all of Takatsuki, 3.756.005 9/1973 Sequin.....Japan 3,777,465 l2/l973 Buzano.... 333L360 8/!974 Horvath 57/34 HS X[73] Asslgnee: Asahl Kasel Kogyo Kabushlki h k Kms 053 Japan PrimaryExaminer-D0na|d E. Watkins Filed? Attorney, Agent, or Firm-Armstrong,Nikaido & 21 Appl. No 518,969 wegm" [30] Foreign Application PriorityData [57] ABSTRACT Oct. 29, I973 Ja an 48-I207l5 Bulked yarns which havemany uniform loops and Mar. I9, 1974 Japan 49-30625 snarls, and areexcellent in spun yarn hand can be obtained by twisting plural yarnshaving difference in [52] U.S. Cl. 57/157 TS; 57/[60 length of 3 to 40%in an optional direction at a twist Int 002G U D026 U D026 /3coefficient of 10 to I40, rubbing thus twisted yarns to Field of Search57/157 157 I57 form loops and snarls in the longer filament yarn, and

57/l40 BY, 160, 77.4, 34 R, 34 HS, 3, 6, l2, subsequently additionallytwisting the yarns in the di- 144; 28/67 rection of the first twistingso that the twist coefficient becomes at least 5 to set the loops andsnarls formed [56] References Cited by the rubbing action.

UNITED STATES PATENTS 12 Claims, 6 Drawing Figures 3,357,l7l l2/l967Marshall 57/l60 TWIST ING RUBBING TWIST ING REMAINING TWISTS ADDITIOJALTWISTING UNTWISTING WRUBBING ADDITIONAL TWlSTING UNTWISTING 'VRUBBINGADDITIONAL TWISTING U.S. Patent Dec. 30, 1975 Sheet 1 of3 3,928,958

FIG.

U.S. Patent Dec. 30, 1975 Sheet 2 0f3 3,928,958

FIG. 2

N A U T l'ol'z 41's [820 DIFFERENCE IN LENGTH (95) FIG. 3

GRADE mwhm 2'o4b osb lol'zol lololo TWIST COEFFICIENT U.S. Patent Dec.30, 1975 Sheet 3 0f 3 3,928,958

FIG.4

TWIST ING RUBBING ADDITIGIAL TWISTING TWISTING UNTWISTING .1 VRUBBINGREMAINING ADDITIONAL TWIST "\G TWISTS RUBBING ADDITIONAL TWISTINGIREMAINING TWISTS FIG. 6

METHOD FOR PRODUCING SPUN YARN-LIKE BULKED YARNS The present inventionrelates to a method for producing spun yarn-like bulked yarns having anumber of loops and snarls. More particularly, it relates to a methodfor producing spun yarn-like bulked yarns by subjecting filament yarnsto suitable twisting and rubbing actions to form a number of loops andsnarls without using turbulent air-stream device.

Conventionally, bulked yarns have been produced by air-jet method whichcomprises jetting high pressure air or steam to filament yarns to form anumber of loops and snarls on the surface of the filament yarns. Thusobtained bulked yarns have been well known under the tradename ofTaslan".

However, according to the method for producing bulked yarns by air-jet,slight variations in shape and size of jetting nozzle, jetting pressureand yarn path have great influence on formation of loops and snarls.Therefore, control of manufacturing process and uniformity of yarnquality is difficult. And also, only a part of energy of jetted fluidcontributes to formation of loops and snarls of filament yarns andpowder transmission efficiency is low and cost for production becomeshigher.

Such being the case, it has been strongly demanded to establish a methodfor economically producing bulked yarns having uniform loops and snarlswithout using the air-jet method.

Conventionally, for imparting spun yarn-like hand to filament yarns,besides said Taslan finishing there has been proposed a method whichcomprises forming torsional loops in filament yarns by employingcomplicated two-stage false twisting method with utilization of thetorsion of filaments generated by false twisting. However, according tosuch method, control of yarn bulkiness is very difficult and stableoperation cannot be attained Recently, a method for producing bulkedyarns having loops which uses balloon generated by overfeeding the yarnsat false twisting is proposed. However, this method causes greatvariation in yarn tension and it is also difficult to effect stableoperation.

The inventors have made intensive research in an attempt to overcome thedefects in the conventional techniques to accomplish a novel method forproducing bulked yarns having suitable loops and snarls in a stableoperation without using turbulent air-stream device as required forTaslan finishing.

That is, the object of the present invention is to pro vide a method forproducing spun yarn-like bulked yarns which comprises subjectingfilament yarns having difference in length to suitable twisting andrubbing action to form a number of loops and snarls and which can bestably operated in a high efficiency and in low cost.

That is, the present invention relates to a method for producing spunyarn-like bulked yarns which comprises either twisting in an optionaldirection plural yarns having difference in length of 3 to 40% at atwist coefficient of 10 to 140, or twisting the yarns to a suitableextent in an optional direction and then untwisting the twisted yarns sothat the number of the untwisting is below said first twist number and aremaining-twist coefficient (this is defined hereinafter) is in a rangeof 10 to 140, and subjecting the twisted yarns to rubbing 2 to formloops and snarls in longer yarn, and subsequently subjecting the twistedyarns to additional twisting in the direction of the first twist in atwist coefficient of at least 5 to set said loops and snarls generatedby the rubbing.

According to the present method, plural yarns having difference inlength of 3 to 40% are twisted at a given twist coefficient range, thenare rubbed to form loops and snarls in longer yarn and simultaneously toform core yarn of shorter yarn, thereafter additional twist is given tothe yarns to set the position of loops and snarls formed by rubbing.

Size and amount of the loops and snarls on the bulked yarn obtained inthe present invention can be optionally controlled by suitably adjustingthe difference in length of the initial yarns, number of twist given onthe yarns and amount of rubbing.

The above and other features of the method of the present invention willbe further understood from the following description when read inconnection with the accompanying drawing: wherein,

FIG. 1(a), (b), (c), (d) and (e) are photographs (:25) of side view ofspun yarn-like bulked yarns ob tained by the method of the presentinvention and are graded into five grades depending upon degree of theloops and snarls, namely, (a) is the lst grade, (blis the 2nd grade, it)is the 3rd grade, (d) is the 4th grade and (e) is the 5th grade;

FIG. 2 is a characteristic diagram which shows rela tion between thedifference in length of the yarns and formation of loops and snarls;

FIG. 3 is a characteristic diagram which shows relation between thetwist coefficient and formation of loops and snarls;

FIG. 4 shows an embodiment of the steps of twisting rubbing additionaltwisting in the present in vention; and

FIGS. 5 and 6 are schematic views of examples of apparatus for theproduction of the bulked yarns in accordance with the present invention.

As is clear from FIG. 1. yarns of the lst grade have relatively smallamount of loops and snarls and with the order of the 2nd grade, the 3rdgrade and the 4th grade, degree of formation of loops and snarlsgradually increases. Yarns of the 5th grade have considerably greateramount of loops and snarls and are the highest in bulkiness.

The yarns of said lst to 5th grades have spun yarnlike hand andexcellent bulkiness, but those of the 2nd to 5th grades are especiallypreferred.

The yarns of below the lst grade have extremely low degree of loops andsnarls and are inferior in spun yarn-like hand.

In the case of the yarns of higher than the 5th grade. the so-calledneps are apt to partially occur to result in ununiform yarns.

The method of the present invention will be more detailedly explainedbelow.

First of all, it is necessary to use combination of groups of pluralyarns different in length by 3 to 40%, preferably 3 to 20%. The longeryarn is for producing loops and snarls in the bulked yarns. In thiscase, it is desirable requirement for obtaining bulked yarns having manyuniform loops and snarls and excellent spun yarn-like hand to employyarn consisting of many non or soft twisted filaments.

On the other hand, the shorter yarns constitute cores of bulked yarnsand any kinds of yarns such as spun 3 yarns or filament yarns ofnatural, regenerated or synthetic fibers and furthermore, monofilamentyarns, hard twist yarns, bulked and crimped yarns may be used. Kind ofthe yarns may be optionally determined depending upon end use of thebulked yarns to be produced.

The method for imparting the difference of 3 to 40% in length of yarnsand the method for twisting the yarns in an optional direction are asfollows:

The method for imparting difference in length.

l. Using a doubling machine, a doubling twister, a ring twister, a fancytwister or a covering twister capable of respectively adjusting feedingamount of yarns, a difference is positively given in length of two yarnsand the two yarns are then twisted with or without doubling.

2. Yarns consisting of filaments different in heat shrinkage or yarnsdifferent in heat shrinkage are doubled and heat treated before or aftertwisting step to shrink to cause difference of 3 to 40% in length.

3. Difference in length of two yarns is given by the difference offeeding amount of two yarns and by the combination of two differentyarns different in heat shrinkage. Due to these two factors, adifference of 3 to 40% is obtained in length of the yarns.

When difference in length is to be obtained by adjusting the feedingamount of the yarns as mentioned in (I), any combination of yarns may beemployed if the longer yarn meets the necessary requirements. On theother hand, when difference in heat shrinkage is utilized, combinationof yarns capable of resulting in difference of substantially 3 to 40% inlength after heat treatment must be chosen. Examples of the combinationof yarns in this case are those of highly shrinkable fibers capable ofeasily shrinking with heat such as polyamide, polyester, polyolefin,polyacryl fibers and their bicomponent fibers, and low shrinkable fibersof regenerated fibers such as viscose rayon, cupra fibers, etc. In thecase of the same kind of synthetic fiber yarns, these-are rendereddifferent in heat shrinkage by difference in drawing ratio, differencein viscosity and addition of a third component in production of yarnsand thus obtained yarns are suitably combined. Furthermore, thecombination of groups of plural yarns having different length may notnecessarily comprises combination of two or more of same or differentkind of yarns as mentioned above, but the bulked yarns may also beproduced from two kinds of filaments different in heat shrinkage andsimultaneously spun as a single yarn, or mixed yarns obtained by openingtwo kinds of yarns and mixing them. Therefore, groups of plural yarns"in the present invention also includes the latter two cases.

Next, an explanation will be given with reference to the requirementthat a difference of 3 to 40% in length of yarns must be imparted to theyarns. As described before, difference in length of yarns is veryimportant for formation of loops and snarls. The difference in lengthcan be considered to be a latent requirement which determines size andamount of loops and snarls and the rubbing action in the post treatmentis considered to be an acutallized requirement for forming loops andsnarls. According to the inventors experiment, if the yarns have adifference in length of at least 3%, loops and snarls of about the 1stto 2nd grades can be formed by increasing the amount of rubbing at thepost treatment, but when the difference in length is less than 3%, loopsand snarls are only slightly formed and spun yarn-like bulked yarnsintended by the present invention cannot be obtained.

When the yarns are doubled and twisted under the conditions that thedifference in length exceeds 40%, neps are apt to be formed by rubbingand the loops and snarls of yarns become very ununiform. Therefore, inorder to produce spun yarn-like bulked yarns having stable quality, itis necessary that difference in length of the starting yarns is 3 to40%, preferably 3 to 20%.

The yarns to which the difference in length is positively and previouslyimparted under the conditions as mentioned above must be then twisted ina given amount to obtain cohesion property. However, when difference inlength is imparted utilizing difference in heat shrinkage of yarns, theyarns may be previously twisted and then subjected to shrinkingtreatment to impart substantial difference in length. The number oftwist may be determined depending upon the desired degree of loops andsnarls, but generally it may be obtained in accordance with thefollowing formula:

:1 r/ m wherein;

T The number of twist per meter at Twist coefficient Nm Metric count Ithas become clear by experiments that in the present invention, range ofthe twist coefficient a in said formula is 10 to 140, preferably 20 to110. That is, when the twist coefficient is less than 10 in the presentinvention, cohesion property of yarns having difference in length is notin a preferred state and uniform loops and snarls are not formed in thelonger yarn by the subsequent rubbing treatment and the loops and snarlsare concentrated at a part of the yarns to cause formationn of neps.When the twist coefficient is more than 140, cohesion property becomescomplete and filaments which constitute the longer yarn are notdisassembled by rubbing to make it impossible to form spun yarn-likeuniform loops and snarls.

It is essential that the yarns to which the differences in length hasbeen imparted are twisted in a range of twist coefficient of 10 to 140.It is sufficient that the twist coefficient suffices said rangeimmediately before the subsequent rubbing step. Therefore, the yarns towhich the difference in length has been imparted and which has beentwisted in a twist coefficient of 10 to may be subjected to rubbing atthe subsequent step to develop loops and snarls. Alternatively, yarns towhich the difference in length has been imparted and which have beentwisted at an optional twist number and in an optional direction may beuntwisted in a direction opposite to the direction of said twisting insuch a manner that the untwist number is below the number of said twistto keep the remaining-twist coefficient of thus untwisted yarns at 10 to140 and then the yarns may be subjected to rubbing to develop loops andsnarls. Especially, in the latter case, rubbing is carried outsimultaneously with untwisting. Therefore, rubbing action is extremelygood and substantially no breakage of yarns occurs. Moreover,particularly uniform loops and snarls can be formed.

In the present invention, the yarns to which differ-' ence in length hasbeen given and which are twisted as explained above are then rubbed todevelop loops and snarls. This rubbing can be carried out with anymaterials which have a high abrasion resistance and do not damage theyarns (such material is called rubbing device" hereinafter). The rubbingcauses separation of Tension after rubbing device (g) Amoum of rubbingTension before rubbing device (g) In the present invention, amount ofrubbing is suitably l.] to 20.0. Increase in the amount of rubbing morethan required may damage the yarns. Furthermore, yarn tension beforerubbing device is at least 3g, generally 3 to 40g and preferably 5 tolSg.

In the present invention, thus rubbed yarns must be additionally twistedin the same direction as the first twisting to set the loops and snarlsformed by said rubbing. The number of the additional twist is preferablyat least 5 in terms of twist coefficient. When this twist coefficient issmaller, the loops and snarls are moved due to a slight rubbing to causeformation of neps or ununiform loops and snarls.

As detailedly explained above, according to the present invention, spunyarn-like bulked yarns having loops and snarls of five grades as shownin photographs of FIG. I can be optionally produced depending upon thedegree of difference in length imparted to the initial yarns, the numberof twist and amount of rubbing.

It has been clarified by experiments that correlations between degree ofloops and snarls generated and each of said three factors are as shownin FIGS. 2 and 3.

FIG. 2 shows the contribution of difference in length to generation ofloops and snarls. Thatis, highly shrinkable polyester filament yarns (90/48f) having a dry heat shrinkage of 36% at 180C and polyester texturedyarns (75)24j) were used and degree of figuration of loops and snarlswas observed when the difference in length and amount of rubbing werechanged with number of twist kept at constant (70 in terms of twistcoefficient). Numerals in the graph of FIG. 2 represent amount ofrubbing. As is clear from this FIG. 2, degree of figuration of loops andsnarls considerably varies depending upon difference in length of yarnsand amount of rubbing. With increase in difference in length, amount ofrubbing can be relatively decreased.

FIG. 3 shows the contribution of twist coefficient (which alsocorresponds to remaining-twist coefficient) to generation of loops andsnarls. That is, the same yarns as used in FIG. 2 were used and degreeof figuration of loops and snarls was observed when twist coefficientand amount of rubbing were changed with difference in length (R I8.7l%)kept constant. Numerals in the graph of FIG. 3 represent amount ofrubbing as in FIG. 2. As is clear from the FIG. 3, degree of generationof loops and snarls considerably varies depending upon twist coefficientand amount of rubbing and especially, there is optimum range in twistcoefficient depending upon the yarns used.

For better understanding of the present invention, a model diagram oftwistingrubbing+additional twisting steps in the present invention isillustrated in FIG. 4. In FIG. 4, (a) shows the steps of twisting yarnshaving difference in length in an optional direction at a twistcoefficient of ID to I40, then rubbing said yarns and additionallytwisting in the same direction as the first twisting direction. In FIG.4, (b) shows another embodiment of the steps of twisting the yarnshaving difference in length in an optional direction to a suitableextent, untwisting the twisted yarns in such a manner thatremaining-twist coefficient is within the range of It) to I40, thenrubbing the yarns and thereafter additionally twising the yarns in thesame direction as the first twisting. In this case, amount of untwistingvaries depending upon amount of the first twisting, but in the presentinvention it is sufficient that said yarns are twisted in such a degreeas 10 to I40 in terms of twist coefficient immediately before therubbing and thus the amount of untwisting has no special limitation.Therefore, such steps as shown in (c) in FIG. 4 may be employed.

In other words, the embodiment of (a) in FIG. 4 corresponds to theembodiments (b) and (0) wherein amount of untwisting is zero.

In the present invention, the twist indicated by dotted line in (b) and(c) in FIG. 4 is considered to be remaining twist and twist coefficientin this case is defined as remaining-twist coefficient.

Next, one example of the apparatus for carrying out the method of thepresent invention will be explained with reference to the drawings. InFIG. 5, yarns l to which a difference in length of 3 to 40% has beengiven and which have been twisted are set in a ring twister and arubbing device 3 is provided between feed roller 2 of said ring twisterand twisting part 4. By said rubbing device 3, the yarns are rubbed toform loops and snarls and subsequently the yarns are additionallytwisted in the twisting part 4. In the case of using yarns which utilizedifference in heat shrinkage, a heater is provided before or after thefeed roller 2 to obtain a difference in length of 3 to 40%.

Another method for practicing the present invention is illustrated inFIG. 6. In FIG. 6, yarns 5 which comprise combination of two kinds ofyarns different in heat shrinkage and which have been twisted in anoptional direction are allowed to pass through heater 6 to shrink onekind of the yarns to impart a difference in length of substantially 3 to40% and subsequently the yarns are allowed to pass through and contactwith a cylindrical rotator which is rubbing device 7, whereby falsetwist and rubbing are imparted to the yarns. That is, a difference inlength is imparted to substantially twisted yarns and then the yarns arecontinuously subjected to untwisting-*rubbingtwisting. When the methodas shown in FIG. 6 is employed, rotating direction of the rubbing devicemust be determined so that the yarns are rotated in the direction ofuntwisting immediately before the first twisted yarns contact with therubbing device. The number of twist when contacting with the rubbingdevice must be ID to I40 in terms of the remaining-twist coefficient.Furthermore, the yarns are relaxed between a pair of rollers 8 and 9before and after heater 6 and shrinking percentage of the yarns isdetermined by the velocity difference in rollers 8 and 9, and moreovermove of twists must be prevented by roller 9 between heater 6 andrubbing device 7. This is because if roller 9 is not provided,untwisting torque extends to the heater part to heat-set the twists toresult in yarns having torque as in the usual false twisting.

In the case of using yarns which do not utilize heat shrinkage, there isno need to provide heater 6. This is the reason why the presentinvention is different from 7 the usual false twisting in the object andtechnical construction.

According to the method of the present invention as explained above,spun yarn-like bulked yarns having uniform loops and snarls andexcellent in bulkiness can be economically and stably produced with useof extremely simple apparatus. Furthermore, soft and voluminous knittedfabrics having good warmth retainability is obtained by knitting thebulked yarns obtained by the pesent invention.

The present invention will be illustrated in the following Examples.

EXAMPLE l Highly shrinkable polyester filament yarns (75d/24f) having adry heat shrinkage of 36% at 180C and polyester false twisted yarns(75d/24f) were twisted at S. 400T/M (twist coefficient a 50) in equalfeeding amount by a ring twister. Then, with use of the apparatus asshown in FIG. 6 thus obtained twisted yarn was allowed to pass through aheater at 180C for 1 second with overfeeding of 20% to shrink the highlyshrinkable polyester yarns to result in difference of 18.5% in lengthfrom the polyester false twisted yarns. At this time, the twisted yarnhad a twist number of 480T/M due to the shrinking. Furthermore, saidtwisted yarn was allowed to pass through a rubbing device in the form ofa hollow cylinder, inside of which was made of urethane rubber and whichhad an inside diameter of 25 mm, at a speeed of 400 m/min and was takenup by a take-up apparatus. Said rubbing device was rotated at 4,000 rpmand the yarn was allowed to contact with the rubbing device at a rubbingamount of 4.0 and a tension before rubbing device of 10 g. The number oftwist at that time was about 8.400 T/M and the number of twist of thefinal bulked yarn was 8.483 T/M. Thus obtained bulked yarn was spunyarn-like soft yarn having loops and snarls which was graded as the thgrade of (e) in FIG. 1. Furthermore, said bulked yarn was knitted into afabric of Pont-de-Rome by a tubular knitting machine of 18 gauges toobtain ajersey having wool-like soft hand. Said bulked yarns wereadditionally twisted at S. l ,300 T/M and were arranged as warp and weftat a warp density of 39 yarns/cm and a weft density of 26 yarns/cm toweave a georgette crepe. This fabric had extremely irregular surface andbulkiness, but had markedly light hand and high elasticity.

EXAMPLE 2 Highly shrinkable polyester filament yarns (90 d/48f) having adry heat shrinkage of 36% at 180C and cupra filament yarns (75d/45f)were twisted at 2.400 T/M (a 54) by a ring twister in an equal feedingamount. Then, using the apparatus as shown in FIG. 6, thus obtainedtwisted yarn was heat treated at 225C for about 0.l5 second withoverfeeding by 20% into the heater to shrink the highly shrinkablepolyester filament yarns, whereby a difference of substantially 20% inlength of the highly shrinkable polyester filament yarns and the cuprafilament yarns was obtained and the number of twist was 2.470 T/M.Subsequently, using the same rubbing device as used in Example 1, saidtwisted yarn was allowed to contact with said rubbing device rotated at4,000 rpm at a yarn speed of 400 m/min, rubbing amount of 3.7 andtension before the rubbing device of g. At that time, the number oftwist was about 2.420 T/M. The final number of twist of thus obtainedbulked yarn was 2.470 T/M and filaments of cupra filament yarns weredisintegrated (opened) with the polyester filament yarns as core to formloops and snarls which were of about the 4th grade of (d) in FIG. 1. Aknitted fabric made of thus obtained bulked yarns was excellent inhygroscopicity, had smooth touch and was suitable as underwears and babywears.

EXAMPLE 3 Wool yarns of 64 metric counts and polyester false twistedyarns of 100 d/36f were twisted at 2.350 T/M (a 56) by a ring twisterwith the feeding amount of said polyester false twisted yarns beinggreater by 10% than that of said wool. Thereafter, thus obtained twistedyarn was allowed to pass through the same apparatus as shown in FIG. 6without the heater, contacting with the same rubbing device as inExample I rotating at 4,000 rpm at a yarn velocity of 400 m/min, arubbing amount of 7.0 and a tension before rubbing device of 8g. At thattime, the number of twist was 2.300 T/M. The final number of twist ofthus obtained bulked yarn was 2.350 T/M and the polyester false twistedyarns were entangled with the wool as core. Thus obtained bulked yarnhad high elasticity and were classified as the 4th grade of (d) in FIG.1.

EXAMPLE 4 Polyester filament yarns of 75d/36f and Nylon 66 filamentyarns of 70d/34fwere twisted at 8.300 T/M (a z 48) by a ring twisterwith the feeding amount of the nylon 66 filament yarns being larger by6% than that of the polyester filament yarns. Then, thus obtainedtwisted yarn was allowed to pass contacting with the rubbing deviceprovided in the ring twister as shown in FIG. 5 at a rubbing amount of5.0 and a tension before rubbing device of 7g. Subsequently, the yarnwas additionally twisted at 8.80 T/M to obtain a bulked yarn. Saidbulked yarn had loops and snarls of about the 3rd grade of (c) inFIG. 1. Furthermore, said bulked yarn was knitted to obtain a graceful,tough and soft knitted fabric which resembled wool.

EXAMPLE 5 Polyester filament yarn of d/36fwas twined around a core yarnof the same kind of polyester filament yarn by a covering twister toimpart difference in length between the two filament yarns. Thusobtained cove red yarn had a twist number of 2.500 T/M (a z 65) and adifference in length of 5% between the two filament yarns. Thus obtainedcovered yarn was allowed to pass contacting with the rubbing deviceprovided in the ring twister as shown in FIG. 5 at a rubbing amount of8.8 and a tension of 4g before rubbing device to rub the yarn. The yarnwas then additionally twisted at 300 T/M in the direction of Z to obtaina bulked yarn of about the 2nd grade of (b) in FIG. 1.

What is claimed is:

l. A method for producing spun yarn-like bulked yarns which comprisestwisting plural yarns having difference in length of 3 to 40% in anoptional direction at a twist coefficient of I0 to I40, rubbing thustwisted yarns to form loops and snarls in longer filament yarns andsubsequently additionally twisting the yarns in the direction of thefirst twisting so that the twist coefficient becomes at least 5 to setthe loops and snarls formed by the rubbing action.

2. A method for producing spun yarn-like bulked yarn which comprisestwisting plural yarns having differcnce of 3 to 40% in length to asuitable extent in an optional direction, then untwisting the twistedyarns in such a manner that the number of the untwisting is below thenumber of the first twisting and remainingtwist coefficient is withinthe range of 10 to I40, rubbing the yarns to form loops and snarls inlonger filament yarns and subsequently additionally twisting the yarnsin the direction of the first twisting so that the twist coefficientbecomes at least 5 to set the loops and snarls formed by the rubbingaction.

3. A method according to claim 2, wherein untwisting, rubbing andadditional twisting are continuously carried out.

4. A method according to claim 1, wherein the difference in length ofyarns is 3 to 5. A method according to claim 1, wherein the differencein length is imparted to the yarns by difference in feeding amount ofthe yarns.

6. A method according to claim 1, wherein the difference in length isimparted to the yarns by difference in heat shrinkage of the yarns.

7. A method according to claim 1, wherein the difference in length isimparted to the yarns by combination of difference in feeding amount anddifference in heat shrinkage.

8. A method according to claim 1, wherein the twist coefficient of thefirst twisting is 20 to 110.

9. A method according to claim 1, wherein amount of rubbing defined inthe specification is l.l to 20.0.

10. A method according to claim 1, wherein yarn tension before rubbingdevice is at least 3g.

11. A method according to claim I, wherein the plural yarns arecombination of polyester filament yarns different in heat shrinkingcharacteristics.

12. A method according to claim 1, wherein the plural yarns arecombination of highly shrinkable syn thetic fibers and low shrinkableregenerated fibers.

1. A method for producing spun yarn-like bulked yarns which comprises twisting plural yarns having difference in length of 3 to 40% in an optional direction at a twist coefficient of 10 to 140, rubbing thus twisted yarns to form loops and snarls in longer filament yarns and subsequently additionally twisting the yarns in the direction of the first twisting so that the twist coefficient becomes at least 5 to set the loops and snarls formed by the rubbing action.
 2. A method for producing spun yarn-like bulked yarn which comprises twisting plural yarns having difference of 3 to 40% in length to a suitable extent in an optional direction, then untwisting the twisted yarns in such a manner that the number of the untwisting is below the number of the first twisting and remaining-twist coefficient is within the range of 10 to 140, rubbing the yarns to form loops and snarls in longer filament yarns and subsequently additionally twisting the yarns in the direction of the first twisting so that the twist coefficient becomes at least 5 to set the loops and snarls formed by the rubbing action.
 3. A method according to claim 2, wherein untwisting, rubbing and additional twisting are continuously carried out.
 4. A method according to claim 1, wherein the difference in length of yarns is 3 to 20%.
 5. A method according to claim 1, wherein the difference in length is imparted to the yarns by difference in feeding amount of the yarns.
 6. A method according to claim 1, wherein the difference in length is imparted to the yarns by difference in heat shrinkage of the yarns.
 7. A method according to claim 1, wherein the difference in length is imparted to the yarns by combination of difference in feeding amount and difference in heat shrinkage.
 8. A method according to claim 1, wherein the twist coefficient of the first twisting is 20 to
 110. 9. A method according to claim 1, wherein amount of rubbing defined in the specification is 1.1 to 20.0.
 10. A method according to claim 1, wherein yarn tension before rubbing device is at least 3g.
 11. A method according to claim 1, wherein the plural yarns are combination of polyester filament yarns different in heat shrinking characteristics.
 12. A method according to claim 1, wherein the plural yarns are combination of highly shrinkable synthetic fibers and low shrinkable regenerated fibers. 